The AAA Foundation for Traffic Safety analyzed cannabis use by drivers in one of those states, Washington, and found that the proportion of drivers involved in fatal crashes who had recently used marijuana more than doubled after Washington legalized the drug for recreational use. In addition, there’s currently no easy way to test whether a driver is impaired by marijuana: Unlike alcohol, it can’t be determined by breath or blood tests.

Fatal crashes involving drivers who recently used marijuana doubled in Washington after the state legalized the drug. Washington was one of the first two states to legalize the recreational use of marijuana, and these findings serve as an eye-opening case study for what other states may experience with road safety after legalizing the drug.

The damaging effects remain even if the person stops smoking the drug
· Teenagers are at particular risk because their brains are still developing
· Smoking cannabis affects critical thinking and memory
· Researchers warn that stronger varieties today are causing more damage

The authors review literature showing that marijuana impairs driving, increasing the risk of being involved in a car accident and that these risks are further enhanced when combining marijuana with alcohol.